Navigational system with a graphical scratchpad filler

ABSTRACT

A navigation system takes a graphical input and translates it into an alpha-numeric entry generally including latitude and longitude information. The system interprets the graphical entry, determines if a waypoint already exists or is depicted at the geographical location identified by the graphical entry and creates a new waypoint if no waypoint already exists or is depicted at the geographical location.

FIELD OF THE INVENTION

The invention generally relates to electronic data entry systems andspecifically to electronic data entry systems with graphical scratchpadfillers for use in aircraft navigation systems.

BACKGROUND

Flight management in large commercial aircraft generally includes aflight management system (FMS). The FMS typically includes a centralcomputer unit which integrates flight information and enables the pilotto manipulate flight information. Flight information may include, forexample, aircraft position data, flight plan data, instrument approachinformation, and/or any other information which may pertain to flightmanagement.

The FMS is generally connected to some sort of display unit, such as,for example, a central display unit (CDU), with which the FMS displaysflight management information for use by the pilots. The CDU generallyhas an area on the screen which displays information prior to entry bythe pilot called a scratchpad. The scratchpad displays characters asthey are entered on a keyboard by the pilot. Thus, the pilot is able tocheck his/her data entry work prior to entry into the FMS.

For example, when interacting with a navigation system, the pilotgenerally enters any needed data into the FMS via the keyboard. Flightplan information generally includes, but is not limited to, waypoint andleg information. Waypoints are series of points that, when connected,identify a flight path. Therefore, modifications to the flight path (orflight plan) generally include modifications to and additions ordeletions of waypoints and/or waypoint data. Waypoints may bepre-existing, pre-defined waypoints generally approved by some sort ofauthoritative body, such as the FAA, or the waypoints may be userdefined. Waypoint information generally includes a waypoint name, anidentifier code, and latitude and longitude information, among otheritems.

When the pilot needs to modify, add, and/or delete flight plan data,he/she generally enters waypoint information into the FMS and views theinformation on the scratchpad area of the CDU. The pilot generally mustenter alpha-numeric characters of some sort to identify the waypoint.Another way to identify a waypoint is to define the new waypoint as abearing and distance from an already defined waypoint. This method ofwaypoint identification also involves entering alpha-numeric charactersinto the scratchpad.

The process of determining waypoint information and entering it into theFMS via the CDU and alpha-numeric characters is both time consuming andrequires considerable cognitive effort by the pilot.

The present invention is directed to overcoming one or more of theproblems or disadvantages associated with the prior art.

SUMMARY

An aircraft navigational system with a graphical scratchpad filler isprovided including a processor which runs a software program, anelectronic display which displays navigational data, a flight managementcomputer including a central display unit with a scratchpad area, and acursor control device. The user may use the cursor control device tocontrol a cursor on the electronic display and select points on theelectronic display for entry into the scratchpad area of the centraldisplay unit.

A method of filling a scratchpad area on a central display unit isprovided, including selecting a location on an electronic display with acursor control device, converting the selected location to latitude andlongitude coordinates, and comparing the latitude and longitude to a setof displayed points on the electronic display. Either the latitude andlongitude or one of the points displayed on the electronic display maybe sent to the scratchpad area on the central display unit

The features, functions, and advantages can be achieved independently invarious embodiments of the present invention or may be combined in yetother embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an aircraft and a flight deck within the aircraft.

FIG. 2 is a schematic diagram of one embodiment of a graphicalscratchpad filler.

FIG. 3 is an example of a Flight Management Computer including ascratchpad area.

FIG. 4 is an example of a navigational display.

FIG. 4A is the navigational display of FIG. 4 showing a temporarywaypoint symbol.

FIG. 5 is an example of one embodiment of a logic diagram illustratinghow the software of the graphical scratchpad filler may operate.

DETAILED DESCRIPTION

Turning now to FIG. 1, an aircraft 10 generally includes a flight deck15 from which pilots may control the operation of the aircraft 10. Theflight deck 15 may include stations 20 for one or more pilots, one ormore electronic displays 30 and at least one cursor control device (CCD)40.

FIG. 2 illustrates one embodiment of a graphical scratchpad filler 100.The graphical scratchpad filler 100 may be integrated with a flightmanagement computer (FMC) 110 which may have a memory 112 containing asoftware program 114. The memory 112 may also include a database 115which may include waypoint information. The FMC 110 may be operativelyconnected to a central display unit (CDU) 120 which may be an electronicdisplay for displaying flight management information. The FMC 110 mayalso be operatively connected to the cursor control device (CCD) 40. TheCCD 40 may enable the pilots to control a cursor on a navigationaldisplay for selection and entry of information into a scratchpad area310 (FIG. 3) of the FMC 110.

Although the components of the graphical scratchpad filler 100 have beendescribed with reference to aircraft systems, the components of thegraphical scratchpad filler 100 may be more general in nature, forexample, a computer of any sort could be substituted for the FMC 110 andan electronic display of any sort may be substituted for the CDU 120.Additionally, the electronic display may be, for example, a cathode raytube (CRT) display, a liquid crystal display (LCD), a plasma display, aprojection display, a touch screen display, or any other type ofelectronic display.

FIG. 3 depicts one embodiment of the FMC 110 that may be integrated withthe graphical scratchpad filler 100 of FIG. 2. The FMC 110 may have aCDU 120 including a scratchpad area 310, line select keys 304 and entrykeys 306. Generally, flight management information is displayed on theCDU 120 for reference and manipulation by the pilot. The pilot entersdata into the FMC 110 via the line select keys 304 and the entry keys306. The line select keys 304 may allow the pilot to select options orchoices available on the CDU 120. If the pilot needs to enter data intothe FMC 110, for example, new waypoint data, the data entry keys 306,which may represent alpha-numeric characters similar to a keyboard, maybe used for data entry. When the pilot enters data via the entry keys306 (and in some cases the line select keys), the entries appear in thescratchpad area 310, and this may allow the pilot to check his/her workprior to execution. Final entry of data from the scratchpad area 310into the FMC 110 may be accomplished with an execute key or an enter key(neither shown), or by selecting one of the line select keys 304.

FIG. 4 is an example of a navigational display (ND) 400. The ND 400 maybe any type of electronic display which displays positional informationfor an aircraft and/or flight plan information for the aircraft. The ND400 may also include a partial compass rose 412 and an aircraft headingand/or track indication 414. An aircraft flight plan generally includeswaypoints 430 and legs 420 a, 420 b, 420 c which connect the waypoints.Additionally, different types of waypoints may be displayed, activewaypoints 430 and background waypoints 440. The active waypoints arelocations, identified by latitude and longitude, over or through whichthe aircraft 410 will pass and which identify points in the flight plan.In other words, the active waypoints 430 define the flight plan and thelegs 420 a, 420 b, 420 c connect those waypoints. Background waypoints440 may also be displayed on the ND 400. Background waypoints 440 may bepredefined waypoints contained within the database of the FMC 110. Thesebackground waypoints 440 may help the pilots change the flight plan inresponse to, for example, air traffic control instructions or weatherdeviations. Additionally, a cursor 450 may be displayed on the ND 400and controlled by the CCD 40.

FIG. 5 shows a logic diagram 500 illustrating a procedure which may befollowed by the graphical scratchpad filler 100 embodied in FIG. 2. Thegraphical scratchpad filler may begin at 510 by determining whether thescratchpad area 310 on the CDU 120 (shown in FIG. 3) is empty, meaningthere is no text currently displayed in the scratchpad area 310. If thescratchpad area is not empty, or is displaying text, the graphicalscratchpad filler 100 may continue to monitor the condition of thescratchpad until the scratchpad is empty.

Once the graphical scratchpad filler 100 has determined that thescratchpad area 310 is empty, the graphical scratchpad filler 100 maythen determine if a waypoint pick mode is active at 512. The waypointpick mode may be a mode within the graphical scratchpad filler 100,selected by the user, which tells the graphical scratchpad filler 100that the user is searching for a waypoint. If the waypoint pick mode isnot active at 512, the graphical scratchpad filler 100 may continue tomonitor the scratchpad area at 510 and the waypoint pick mode at 512. Ifhowever, the waypoint pick mode is active at 512, the graphicalscratchpad filler 100 may then determine whether the waypoint pick modehas been cancelled at 514. If the waypoint pick mode has been cancelledat 514, the graphical scratchpad filler 100 may again monitor thescratchpad area at 510 and the waypoint pick mode at 512.

If the waypoint pick mode has not been cancelled at 514, the graphicalscratchpad filler may convert the position of the cursor 450 on the ND400 (FIG. 4) to a point defined by a latitude and a longitude. Thisconversion may be performed by using the Sodano Equation shown below:

${NewLat} = {a\;{\sin\left\lbrack {\left( {{\sin({refLat})} \times {\cos\left( \frac{\sqrt{{\Delta\; X^{2}} + {\Delta\; Y^{2}}}}{3444.053898} \right)}} \right) + \left( {{\cos({refLat})} \times \left( {\cos\left( {{aran}\frac{\Delta\; X}{\Delta\; Y}} \right)} \right) \times {\cos\left( \frac{\sqrt{{\Delta\; X^{2}} + {\Delta\; Y^{2}}}}{3444.053898} \right)}} \right)} \right\rbrack}}$${NewLong} = {{{resolve}\mspace{14mu}{to}} + \text{/} - {180\left( {{refLong} + \left( {H \times a\;{\cos\left( \frac{\cos\left( \frac{\sqrt{{\Delta\; X^{2}} + {\Delta\; Y^{2}}}}{3444.053898} \right.}{{{Cos}({refLat})}{x\left( {\cos({Lat\_ New})} \right)}} \right)}} \right)} \right)}}$

Where:

New Lat is the latitude of the cursor point

New Long is the longitude of the cursor point

reflat is a reference latitude

reflong is a reference longitude

ΔX is the difference in the X direction between the reference point andthe cursor position on the ND

ΔY is the difference in the Y direction between the reference point andthe cursor position on the ND

This conversion may also be performed by any equivalent equation thatprojects a point on a sphere onto a plane.

After the graphical scratchpad filler 100 has converted the cursorposition to a point of latitude and longitude at 516, the cursor may bechecked at 518 to determine whether a displayed point, such as, forexample, a waypoint, an airport, a NAVAID, a station, or any otherdisplayed point, is located within a preset distance from the cursorlocation. In one embodiment, the preset distance is a 0.25 inch radiusabout the cursor 450. In this way, the user may effectively “filter”which points may be checked by selecting the appropriate level of detailon the ND 400. For instance, if the user would like to check for anybackground waypoints 440 which may allow him/her to modify the flightplan to avoid weather, the user may select background waypoints 440 fordisplay on the ND 400 before selecting the waypoint pick mode. In thisway, the background waypoints may be displayed on the ND 400 and beavailable for the graphical scratchpad filler 100 to check. Conversely,if the user would like to check for a diversion airport, he/she mayselect airports or stations for display on the ND 400 prior to selectingthe waypoint pick mode on the graphical scratchpad filler 100. In thisway, the user may selectively “filter out” unwanted data on the ND 400and thereby speed up the selection process and ultimately the process ofmodifying the flight plan if desired.

If a displayed point is located within the preset distance of the cursor450, the displayed point may be highlighted and the identification ofthe point shown on the ND 400 at 520. Identification of a point inaviation generally includes a one to seven letter code which uniquelyidentifies the point. The code may be stored in a database along withinformation specific about the point, such as, for example, latitude andlongitude, point type (i.e. beacon, TACAN, VOR, VORTAC, airport, etc.),magnetic variation, servicing agency, frequency, or any other desiredinformation about the point.

The user may select the highlighted displayed point on the ND 400 at 522by activating the cursor control device 130 (FIG. 2). Once selected, thegraphical scratchpad filler 100 may send the point identification (twoto four letter code) to the scratchpad area 310 of the FMC 110 (FIG. 3)at 524 and place a temporary waypoint symbol 451 (FIG. 4A) on the ND 400with the point identification at that location at 531. Once the data hasbeen sent to the scratchpad area 310, the user may then modify theflight plan per normal operation of the FMC 110.

If, however, there is no displayed point on the ND 400 within thepredefined distance of the cursor at 518, the graphical scratchpadfiller 100 may display the latitude and longitude of the point(determined at 516) at 526. Once the latitude and longitude of the pointis displayed at 526, the user may select this latitude and longitude at528 by activating the cursor control device 130. If the user selects thelatitude and longitude at 528, the latitude and longitude may be sent tothe scratchpad area 310 of the FMC 110 at 530 and a temporary waypointsymbol 451 with the latitude and longitude may be placed on the ND 400at the selected location at 533. Again, once the latitude and longitudeis sent to the scratchpad area 310, the user may modify the flight planper normal operation of the FMC 110.

Other aspects and features of the present invention can be obtained froma study of the drawings, the disclosure, and the appended claims.

1. An aircraft navigation system comprising: a processor operativelycoupled to an electronic display that graphically displays flight planinformation; a flight management computer, the flight managementcomputer including a central display unit for alpha-numericallydisplaying flight plan information; a memory accessible by the processorand adapted to store a software program and a database; and a cursorcontrol device for controlling a cursor on the electronic display,wherein the software program is adapted to interpret a selection on theelectronic display made by a user with the cursor control device, toconvert the selection on the electronic display to latitude andlongitude coordinates, to compare the latitude and longitude coordinatesof the selection on the electronic display to a displayed navigationalpoint on the electronic display, to fill a scratchpad area on thecentral display unit with information regarding the displayednavigational point on the electronic display if the displayednavigational point on the electronic display is within a predetermined,distance of the latitude and longitude coordinates of the selection onthe electronic display, to place a temporary waypoint symbol on theelectronic display with the latitude and longitude coordinates of thedisplayed navigational point on the electronic display if the displayednavigational point on the electronic display is within the predetermineddistance of the latitude and longitude coordinates of the selection onthe electronic display, to fill the scratchpad area on the centraldisplay unit with the latitude and the longitude coordinates of theselection on the electronic display if the displayed navigational pointon the electronic display is not within the predetermined distance ofthe latitude and longitude coordinates of the selection on theelectronic display, and to place the temporary waypoint symbol on theelectronic display with the latitude and longitude coordinates of theselection on the electronic display if the displayed navigational pointon the electronic display is not within the predetermined distance ofthe latitude and longitude coordinates of the selection on theelectronic display.
 2. The aircraft navigation system of claim 1,wherein the processor is part of a flight management system.
 3. Theaircraft navigation system of claim 1, wherein the electronic display isone of a cathode ray tube (CRT), a liquid crystal display (LCD) a plasmadisplay, and a projection display.
 4. The aircraft navigation system ofclaim 3, wherein the electronic display incorporates touch-screentechnology and wherein the cursor is controlled by a user touching thedisplay.
 5. The aircraft navigation system of claim 1, wherein theprocessor checks the electronic display to determine if the displayednavigational point on the electronic display is located within thepredetermined distance of the latitude and longitude coordinates of theselection on the electronic display.
 6. The aircraft navigation systemof claim 5, wherein the processor determines the selection on theelectronic display to be the same as the navigational point on theelectronic display if the navigational point on the electronic displayfalls within the predetermined distance of the latitude and longitudecoordinates of the selection on the electronic display.
 7. The aircraftnavigation system of claim 6, wherein the predetermined distance is 0.25inches.
 8. The aircraft navigation system of claim 1, wherein thesoftware program converts the selection on the electronic display tolatitude and longitude coordinates using a Sodano Equation.